title: A new flavonoid glycoside and other chemical constituents from leaves of Rosa davurica and their antioxidant activity.
abstract: A 70% ethanol extract from the leaves of Rosa davurica showed significant antioxidant activity in both superoxide anion and 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical-scavenging assays. Phytochemical study of this extract resulted in the isolation of eight compounds, including a new flavonoid glycoside. The chemical structure was determined by various spectroscopic analyses. The isolated compounds and their structurally related compounds, belonging to two classes: quercetin 3-O-glycosides and gallic acid derivates, were evaluated for their superoxide anion- and DPPH free radical-scavenging activities. These compounds showed significant superoxide anion-scavenging activity with the EC50 values ranging from 1.68 to 18.09 μM, and DPPH free radical-scavenging activity with the EC50 values ranging from 7.18 to 67.62 μM. The structure-activity relationship was also reported.
authors.affiliation: a Faculty of Pharmaceutical Sciences, Toho University , Miyama 2-2-1, Funabashi Chiba 274-8510 , Japan.
authors.forename: Fenghua
authors.initials: F
authors.lastname: Ma
authors.forename: Toshihisa
authors.initials: T
authors.lastname: Onoda
authors.forename: Wei
authors.initials: W
authors.lastname: Li
authors.forename: Tatsunori
authors.initials: T
authors.lastname: Sasaki
authors.forename: Ling
authors.initials: L
authors.lastname: Ma
authors.forename: Qingbo
authors.initials: Q
authors.lastname: Zhang
authors.forename: Kazuo
authors.initials: K
authors.lastname: Koike
mesh_terms: D000975:Antioxidants / Q000302:isolation & purification / Q000494:pharmacology*; D005419:Flavonoids / Q000302:isolation & purification / Q000494:pharmacology*; D006027:Glycosides / Q000302:isolation & purification / Q000494:pharmacology*; D009682:Magnetic Resonance Spectroscopy; D018515:Plant Leaves / Q000737:chemistry*; D027826:Rosa / Q000737:chemistry*; D021241:Spectrometry, Mass, Electrospray Ionization; D013056:Spectrophotometry, Ultraviolet; D017550:Spectroscopy, Fourier Transform Infrared
chemical_list: D000975:Antioxidants; D005419:Flavonoids; D006027:Glycosides